tests/test-double-merge.t

changegroup: move message about added changes to transaction summary

Before that, applying multiple changegroups in the same transaction issued the
message multiple time. This result in a confusing output:

    adding changesets
    adding manifests
    adding file changes
    added 32768 changesets with 60829 changes to 2668 files
    adding changesets
    adding manifests
    adding file changes
    added 8192 changesets with 16885 changes to 1553 files
    adding changesets
    adding manifests
    adding file changes
    added 1020 changesets with 1799 changes to 536 files
    adding changesets
    adding manifests
    ...

Instead, we now only issue the message once at the end of the transaction,
summing up all added changesets, changes and files. The line is identical, but
happens sightly later in the output.

There are other suboptimal behavior around issue multiple changegroup (eg:
progress bar). We'll cover them later.

This impact of lot of test as one would expect, but a two pass check show they
are just the order change we expected.

To deal with "under the hood" bundle application by internal code, we had to
take a slightly hacky move. We could clean that up with a more official way to
enter "under the hood" section, however I want to keep this series simple to get
it landed. This kind of change have a very high bit rot rate since it impact a
lot of test output.

  $ hg init repo
  $ cd repo

  $ echo line 1 > foo
  $ hg ci -qAm 'add foo'

copy foo to bar and change both files
  $ hg cp foo bar
  $ echo line 2-1 >> foo
  $ echo line 2-2 >> bar
  $ hg ci -m 'cp foo bar; change both'

in another branch, change foo in a way that doesn't conflict with
the other changes
  $ hg up -qC 0
  $ echo line 0 > foo
  $ hg cat foo >> foo
  $ hg ci -m 'change foo'
  created new head

we get conflicts that shouldn't be there
  $ hg merge -P
  changeset:   1:484bf6903104
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     cp foo bar; change both
  
  $ hg merge --debug
    unmatched files in other:
     bar
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     src: 'foo' -> dst: 'bar' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: e6dc8efe11cc, local: 6a0df1dad128+, remote: 484bf6903104
   preserving foo for resolve of bar
   preserving foo for resolve of foo
  starting 4 threads for background file closing (?)
   bar: remote copied from foo -> m (premerge)
  picked tool ':merge' for bar (binary False symlink False changedelete False)
  merging foo and bar to bar
  my bar@6a0df1dad128+ other bar@484bf6903104 ancestor foo@e6dc8efe11cc
   premerge successful
   foo: versions differ -> m (premerge)
  picked tool ':merge' for foo (binary False symlink False changedelete False)
  merging foo
  my foo@6a0df1dad128+ other foo@484bf6903104 ancestor foo@e6dc8efe11cc
   premerge successful
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

contents of foo
  $ cat foo
  line 0
  line 1
  line 2-1

contents of bar
  $ cat bar
  line 0
  line 1
  line 2-2

  $ cd ..